Late results of two hundred seventeen femoropopliteal bypasses to isolated popliteal artery segments

Clinical outcomes after balloon angioplasty with Crosser device for heavily calcified common femoral and popliteal artery disease

Data on the mid-term clinical outcomes after endovascular treatment (EVT) using a Crosser catheter (C. R. Bard, Inc.) as a crossing or flossing device for a heavily calcified lesion in the common femoral artery (CFA) or popliteal artery (PA) are lacking. The aim of this study was to investigate the safety and efficacy of EVT using a Crosser catheter for isolated and heavily calcified CFA or PA disease. We retrospectively analyzed 64 consecutive patients (72 lesions; CFA 30, PA 42) who underwent EVT for heavily calcified CFA or PA lesions with Crosser catheters between April 2015 and April 2019. The primary endpoint was clinically driven target lesion revascularization (CD-TLR). The median follow-up was 18.5 months. The mean age of the study population was 70 ± 9.5 years, with a male prevalence of 73.6%. The mean Proposed Peripheral Artery Calcification Scoring System grade was 2.9 ± 0.9. Procedure success, defined as 50% or less residual stenosis without suboptimal results, was achieved in 94.4% of lesions. There were no cases of bailout stenting or target lesion-related complications. After EVT, the 1-year CD-TLR-free rate for CFA and PA lesions was 87.4 and 76.8%, respectively. The corresponding rates at 2 years were 82.2 and 62.8%, respectively. In the multivariate analysis used to define CD-TLR predictors for CFA and PA lesions, hemodialysis was the only independent predictor (HR 3.35, 95% CI 1.02-13.95, P = 0.045). EVT with a Crosser device for heavily calcified CFA and PA lesions seems to be safe and feasible.

Critical Limb Ischemia Secondary to Antiphospholipid Syndrome in a Pediatric Patient: Case Report and Review

BACKGROUND

Antiphospholipid syndrome (APS) is a condition that manifests as venous or arterial thrombosis, as well as complications of pregnancy. APS affecting primarily the arteries is less common when compared to venous complications. We present a case of arterial occlusion resulting in critical limb ischemia (CLI) in a pediatric patient.

METHODS

A 14-year old boy presented with worsening right lower extremity pain and ulcerative lesions of his foot. Laboratory analysis revealed a diagnosis of APS. This case report and review of the literature expands our understanding of arterial manifestations of APS in the pediatric patient.

RESULTS

The patient was discovered to have proximal occlusion of the superficial femoral artery (SFA), the distal popliteal artery, the anterior tibial artery at the mid-calf, and the posterior tibial artery at the ankle. He underwent a common femoral artery to above-knee-popliteal artery bypass with reversed greater saphenous graft. Follow up after over one-year demonstrated an ABI of 1.0 and no evidence of stenosis in the bypass graft on duplex ultrasound (DUS).

CONCLUSIONS

APS is a complex syndrome with a variety of clinical presentations. This case highlights arterial manifestations of APS and reviews the expanding literature to guide improved patient outcomes.

Basic data related to surgical infrainguinal revascularization procedures: a twenty year update

In 1990, Dalman and Taylor published a compilation of reported data that were identified by them as related to infrainguinal revascularization procedures in peripheral vascular surgery during the decade of the 1980s. The intervening 20 years has seen revolutionary advances in the field of peripheral vascular surgery, especially in the adoption of endovascular techniques, and an explosion of data related to emerging technologies in the field of infrainguinal revascularization. The tables in this manuscript reflect the evolution of our surgical knowledge during the turn of the 21st century. The superior patency of autologous saphenous vein in all positions is reaffirmed.

Limb salvage using bypass to the perigeniculate arteries

OBJECTIVE

To describe bypass to perigeniculate vessels for limb salvage.

DESIGN

Retrospective cohort study.

MATERIAL AND METHODS

Between 1995 and 2009, 47 bypass procedures to perigeniculate collateral arteries were performed in 46 patients (15 women, 31 men; median age, 68 years). All patients presented with critical ischaemia (tissue loss in 87.5%, rest pain in 12.5%). Mean ankle brachial index was 0.27 ± 0.17. The site of distal anastomosis was the descending genicular artery (DGA) in 23 bypasses (1 bilateral) and the medial sural artery (MSA) in 24. Proximal anastomosis was to the external iliac artery in 2 cases, common femoral artery in 23 cases, superficial femoral artery in 8 cases, deep femoral artery in 8 cases, above-knee poplitaeal artery in 2 cases, and previous graft in 4 cases.

RESULTS

There were four deaths during the immediate postoperative period. Mean follow-up duration was 27 months. Ten patients required major amputation. Mean ankle brachial index post-operatively was 0.60 ± 0.21. At 3 years, primary patency was 74.7 ± 7%, secondary patency was 83.4 ± 8%, and the limb salvage and survival rates were 73.5 ± 7% and 77.4 ± 7%, respectively.

CONCLUSION

Bypass to perigeniculate arteries is a viable treatment option for critical limb ischaemia in selected patients.

Artéria femoral profunda: uma opção como origem de fluxo para derivações infrageniculares

CONTEXTO: Na isquemia crítica, a artéria femoral profunda pode tornar-se a opção mais distal como origem de fluxo para derivações distais em casos de oclusão da origem da artéria femoral superficial associada a prega inguinal hostil. OBJETIVO:Avaliar, retrospectivamente, a artéria femoral profunda como doadora de fluxo para derivações infrageniculares. MÉTODOS: De 2000 a 2005, 129 derivações infrageniculares apresentaram anastomose proximal nas artérias femorais, comum (40), superficial (72) e profunda (17). O presente estudo teve como foco a artéria femoral profunda, e suas indicações foram: prega inguinal hostil (seis casos), limite da extensão do substituto (seis casos) e ambos os fatores (outros cinco casos). Foram abordadas a primeira e a segunda porção em 12 casos e a terceira porção em cinco casos. As cirurgias foram secundárias em 47% dos casos, e os substitutos utilizados foram veias do membro superior em 11 casos, safena interna em cinco e safena externa em um caso. RESULTADOS: No total dos enxertos (129), as estimativas de perviedade primária e salvamento do membro foram: 68,0% e 84,7%, respectivamente, com erro padrão (EP) aceitável (0,1) em 36 meses. Quando o grupo foi estratificado, as artérias femorais comum, superficial e profunda apresentaram resultados comparáveis de perviedade primária (63,3, 70,2 e 64,7%; p = 0,63) e salvamento do membro (83,1, 82,4 e 92,3%; p = 0,78). A perviedade dos enxertos com origem nas porções proximal e distal da artéria femoral profunda, bem como das cirurgias primárias e secundárias, foram comparáveis, sem diferença estatística significante (p = 0,89 e p = 0,77, respectivamente). CONCLUSÃO: A artéria femoral profunda mostrou ser acessível e efetiva como origem de fluxo de enxertos infrageniculares, com resultados satisfatórios de perviedade e salvamento do membro.

Peripheral atherectomy in TransAtlantic InterSociety Consensus type C femoropopliteal lesions for limb salvage

BACKGROUND

The optimal therapy for TransAtlantic Societal Consensus (TASC) type C femoropopliteal lesions remains a critical issue in the treatment of infrainguinal occlusive disease. The purpose of this study was to evaluate the outcome of limbs with TASC C femoropopliteal lesions and critical limb ischemia treated with the FoxHollow SilverHawk atherectomy catheter.

METHODS

From September 2004 to September 2005, 18 consecutive femoropopliteal procedures performed in 17 limbs in 16 patients were reviewed. Demographic data, baseline angiographic findings, and indications for the procedures were recorded. Clinical outcomes including symptom resolution and limb salvage were determined for the 17 primary procedures. Hemodynamic improvement was compared by using the paired Student t test. Stenosis-free patency was determined by the Kaplan-Meier method.

RESULTS

The mean age was 72.5 years (range, 47-88 years). Fifty percent of the patients had four or more of the following risk factors: hypertension, diabetes, tobacco use, hyperlipidemia, renal insufficiency, and coronary artery disease. The indication was tissue loss in 13 limbs and rest pain in 4. All patients had a second level of disease, either inflow or tibial/pedal, which was treated concurrently when appropriate. Initial resolution of symptoms was achieved in 12 limbs, and partial healing was achieved in 2 others. Early amputation was necessary in the remaining three patients, but this was likely due to severe inframalleolar disease and advanced forefoot ischemia at the time of presentation. Five patients have remained symptom-free without restenosis at a mean follow-up of 6 months. Two patients have required late amputation for hemodynamic failure. The ankle-brachial index improved from 0.39 +/- 0.08 (mean +/- SEM) before surgery to 0.75 +/- 0.08 in the immediate postoperative period (P = .02). However, it returned toward baseline at 6 months after surgery, with a mean of 0.48 +/- 0.07. Stenosis-free patency of the femoropopliteal segment was 22% at 12 months.

CONCLUSIONS

Peripheral atherectomy can achieve good early clinical and hemodynamic success in patients with TASC C lesions and critical limb ischemia. However, mid-term restenosis rates are high in this challenging cohort of patients.

Surgical Management of Critical Limb Ischemia

At the present time, infrainguinal bypass using autogenous vein is the most effective and durable treatment for chronic limb ischemia caused by long-segment, diffuse, atherosclerotic occlusive disease. Quality of the vein conduit is the most important factor that determines operative success. Preoperative vein mapping is useful to identify an optimal vein conduit as well as to suggest vein segments that should not be explored due to occlusion, significant calcification, poor caliber, or sclerosis. Reversed, nonreversed, and in situ vein bypass grafts all perform equally well, and the choice of technique depends on anatomic considerations and surgeon preference. Bypass grafts originating from inflow sources distal to the common femoral artery may be appropriate in selected cases without compromising graft patency. All vein graft patients should be followed by postoperative, duplex-based graft surveillance. Antiplatelet therapy is indicated in all infrainguinal bypass patients; oral anticoagulation may be worthwhile in selected, high-risk patients, but hemorrhagic risks are significantly increased.

Effect of Warfarin Anticoagulation on Below-Knee Polytetrafluoroethylene Graft Patency

When polytetrafluoroethylene (PTFE) must be used for below-knee bypass to achieve limb salvage, effective anticoagulation with warfarin may improve graft survival. We analyzed our practice of routinely using oral anticoagulation to improve graft patency rates for PTFE grafts to below-knee popliteal and crural vessels in limb salvage procedures. We reviewed our established vascular database from February 1999 through April 2003 to identify those patients who required below-knee and tibial artery bypass with PTFE for critical limb ischemia. All patients were initiated on warfarin anticoagulation postoperatively, with an international normalized ratio (INR) of 2.0-3.0 considered therapeutic. All patients were discharged in the therapeutic range. Life-table analysis and Kaplan-Meier estimates were used to compare primary patency rates with regard to INR and position of distal anastomosis. Cox proportional hazards analysis was performed to compare the patency rates for grafts with therapeutic versus subtherapeutic anticoagulation while correcting for variability in distal runoff. Between February 1999 and April 2003, 74 patients (mean age, 69.2 years; 58% men) had 77 below-knee PTFE bypasses. Indications for operation included rest pain (43), ischemic ulcer (27), and gangrene (7). Patients presenting with occluded grafts more often had a subtherapeutic INR. Patients with a subtherapeutic INR (< or = 1.9) had a median primary graft patency of 6.8 months and those with a therapeutic INR (> or = 2.0) had a median primary graft patency of 29.9 months (p = 0.0007). Analysis by Cox proportional hazards model demonstrated a significantly better graft patency rate in patients with a therapeutic INR regardless of outflow vessel. The patency rates of PTFE grafts to infrageniculate vessels may be improved by effective anticoagulation with warfarin. This improved patency rate may also result in improved limb salvage and further support the use of PTFE grafts for critical limb ischemia when autogenous vein is not available. Predictably, the best results are seen with an INR therapeutic range of 2.0 to 3.0.

Outcome of revascularization procedures for peripheral arterial occlusive disease in Ontario between 1991 and 1998: a population-based study

PURPOSE

We describe the outcome of revascularization procedures used to treat peripheral arterial occlusive disease (PAOD), using population-based administrative data.

METHODS

A retrospective population-based cohort study utilizing administrative databases in Ontario, Canada, was conducted for fiscal years 1991 to 1998 to identify patients who underwent arterial bypass surgery and percutaneous transluminal angioplasty to treat PAOD. The Kaplan-Meier method was used to calculate cumulative survival rate and amputation-free survival rate. To analyze factors that affect these rates, multivariate analysis was performed with Cox proportional hazard models.

RESULTS

Over the study period 15,824 patients underwent bypass operations and 11,548 underwent angioplasty. For patients who underwent bypass surgery, 5-year cumulative survival rate was 61.5% and major amputation-free survival rate was 83.4%, compared with 69% and 92.2%, respectively, for patients who underwent angioplasty. Male sex, older age, diabetes, and heart disease were associated with increased risk for death after revascularization procedures. Increased risk for major amputation after revascularization procedures was associated with male sex, older age, and diabetes, whereas hypertension was linked to decreased risk.

CONCLUSION

To evaluate the long-term outcome of revascularization procedures for PAOD at the population level, survival and major amputation-free survival rates should be used, because they provide more clinically accepted estimates compared with the correlation between utilization rates for revascularization and amputation procedures, which have been used to describe outcome in previously published reports in the literature.

Bypass graft to the midpopliteal artery with a combined anterior and posterior approach

PURPOSE

The medial supragenicular and infragenicular approaches to the popliteal artery were introduced almost 50 years ago and replaced the posterior approach to the popliteal artery for distal graft implantation. We review a contemporary series of bypass grafts to the midpopliteal artery by use of a combined anterior and posterior approach to evaluate its potential clinical benefits.

TECHNIQUE

After the proximal graft anastomosis is constructed, an incision is made in the popliteal fossa to access the midpopliteal artery, the graft is passed into that incision, and all but the popliteal incision is closed. The patient is turned, the midpopliteal artery dissection is completed, and the graft is anastomosed distally.

METHODS

Fifty-seven bypass grafts, implanted distally on the midpopliteal artery by this technique over a 13-year period, chosen in preference to an infragenicular bypass graft in selected patients when a supragenicular bypass was not feasible, were assessed in terms of indications for surgery, conduit type, complications, length of postoperative hospitalization, and graft patency.

RESULTS

Bypass grafting originated from the axillary artery in two cases, the common iliac artery in one case, and the femoral artery in 54 cases. The procedure was performed in five patients with a popliteal trifurcation anomaly, nine patients with a blind popliteal segment, 20 patients with limited length of autologous vein, and five patients with an above-knee graft infection requiring an alternate path for revascularization. Autologous vein was used in 35 and polytetrafluoroethylene (PTFE) in 19 bypass grafts. Three other patients had a composite sequential femoral-popliteal-tibial bypass graft, with PTFE and autologous vein. Postoperative (30 day) complications include one death (composite sequential), one stroke (PTFE), and one graft thrombosis (saphenous vein). The mean postoperative hospitalization for the last 31 patients was 4.2 +/- 3.7 days. In the autologous vein group, the 1-year primary patency rate was 87%, and the primary assisted patency rate was 94%. In the PTFE group, the 1-year primary patency rate was 72%. Two composite sequential grafts remained patent at 1 year.

CONCLUSIONS

Bypass grafting to the midpopliteal artery with a combined anterior and posterior approach offers a safe and effective option to below-knee bypass grafting when an above-knee bypass grafting is not feasible. Compared with the medial infragenicular incision, the posterior incision results in reduced morbidity rates, rapid mobilization, and early hospital discharge.

[Isolated popliteal arteries: results of surgical treatment and causes of failure]

Isolated popliteal artery is defined as an obstruction of a superficial femoral artery with a patent popliteal segment followed by an obstructed distal popliteal artery or a patent leg artery less than 5 cm long.

PURPOSE

The aim of this retrospective study was to report the results of surgical treatment and the causes of failures.

PATIENTS AND METHODS

From 1988 to 1996, 31 patients with isolated popliteal artery were operated on with femoropopliteal bypass. The age of the patients ranged from 45 to 92 years, (mean: 79 years); all had critical ischemia that threatened limb viability. All underwent preoperative arteriography and diagnosis was confirmed by intraoperative arteriography.

RESULTS

In the postoperative course, there were 22 patent bypasses (68%) with minor amputation in five patients, and nine thromboses that required a major amputation in seven patients, a trans-metatarsal amputation in one, and a medical treatment in one. With a mean 37-month follow-up, seven thromboses required a major amputation in five patients, a new bypass in one and a medical treatment in one. The death rate was 34% at two years. The actuarial patency rates of the bypasses were 51% at one year, 38% at two years and 25% at five years. The limb salvage rate was identical. The patency rates were 65% at one, two and five years for venous bypasses and 38%, 13% and 0% respectively for PTFE bypasses. Statistical analysis showed two causes of failure: the absence of a run-off branch and the use of PTFE prostheses. No other statistically significant cause of failure was demonstrated among those analysed. Favourable anatomic conditions for a bypass to a leg artery were not predictive of failure of a femoro-popliteal bypass on the isolated arterial segment.

CONCLUSION

Bypass to isolated popliteal artery is indicated in patients whose limb viability is jeopardized. Results may be considered as satisfactory especially if there is a run-off branch and if a venous graft is available for the bypass.

Secondary distal extension of infrainguinal bypass: long-term limb and patient survival

The potential benefits of secondary distal extension vein grafts required after failing or failed initial infrainguinal bypasses were evaluated. Outcomes of secondary distal extension bypass procedures (n = 58) performed between July 1983 and March 1993 were reviewed. Patients (n = 51) had critical ischemia or tissue loss, with an average of 2.8 previous vascular procedures. The 58 initial infrainguinal bypasses included 38 above-the-knee and 13 below-the-knee femoropopliteal, 5 femorodistal, and 2 popliteal-distal. Thirty-nine of the 58 femoropopliteal grafts were prosthetic. The extension bypasses included popliteal-tibial, graft-tibial, and peroneal-plantar. They were performed for recurrent or persistent ischemia after failed initial infrainguinal bypasses in limbs, and with still-patent bypasses. All extension bypasses were vein conduits. Mean follow-up was 59 (range: 6 to 164) months. The cumulative life-table 5-year survival rate for all patients was 95%. The 27-month limb-salvage rate was 70%. Our findings indicate that patients with advanced peripheral vascular disease may have prolonged survival, and extension bypasses contribute significantly to their limb salvage. Thus, aggressive application of extension bypass to save threatened limbs is supported.

Minimally Invasive Endoscopic Video-Assisted in Situ Bypass: First 15 Cases

The purpose of the present study was to determine the feasibility of endoscopic video-assisted (EVA) in situ bypass with greater saphenous vein (SV) for femorotibial revascularization. Fifteen consecutive patients who underwent EVA lower extremity revascularization were included in the present report. EVA in situ bypass was successfully accomplished in 12 of 15 (80%) patients. Two patients had major SV injuries (endoscopic scissors), and 6 patients had minor SV injuries (dissecting ring, clip applicator, valvulotome). Postoperatively, 2 patients developed subcutaneous abscesses in the thigh graft tunnel, and 5 patients developed minor calf wound necrosis. Eight of 12 (67%) EVA in situ bypasses were patent at 6- to 32-month follow-up (mean, 24 months), and 2 of 12 (17%) patients died with patent EVA in situ bypasses; one other patient experienced EVA in situ bypass thrombosis 6 months postoperatively without further surgical treatment. Ten of 12 (83%) patients who underwent EVA in situ bypass had successful surgical outcomes, and 11 of 12 (92%) avoided major amputation; 1 patient eventually required below-knee amputation because of nonhealing foot lesions despite a patent EVA in situ bypass. We conclude that EVA in situ bypass with SV is a practical technique for limiting the length and number of incisions necessary to completely eliminate SV tributaries. On the basis of experience gained from the present series, we recommend the following: 1) strategic placement of the initial small skin incisions to maximize exposure of the SV and inflow/outflow arteries; 2) beginning gas insufflation into the perivenous space during initial SV dissection, rather than after creation of the perivenous tunnel; 3) no transection of clipped SV tributaries with the endoscopic scissors; 4) minimal use of the dissecting ring to expose the SV and its tributaries, instead using continuous gas insufflation and the balloon dissector; and 5) completion angiography to inspect the bypass graft and runoff.

Diagnosis and treatment of chronic lower extremity ischemia

Chronic lower extremity ischemia is due to progressive atherosclerosis of the aorto-iliac and/or infrainguinal arteries. This disease process is of great importance as millions of patients are affected by lower extremity arterial occlusive disease. Most of these patients are asymptomatic but a growing number of them are symptomatic, with complaints ranging from mild claudication to gangrene. The increasing number of patients affected by lower extremity atherosclerosis is, in part, due to the 'graying' of the general population and to the medical improvements of the past three decades that have allowed patients with generalized atherosclerosis to survive longer. Fortunately, the diagnosis and management of peripheral arterial occlusive disease has also significantly progressed leading to improved graft patency, limb salvage rates, and quality of life for patients.

Isolated femoropopliteal bypass graft for limb salvage after failed tibial reconstruction: a viable alternative to amputation

PURPOSE

Femoropopliteal bypass grafting procedures performed to isolated popliteal arteries after failure of a previous tibial reconstruction were studied. The results were compared with those of a study of primary isolated femoropopliteal bypass grafts (IFPBs).

METHODS

IFPBs were only constructed if the uninvolved or patent popliteal segment measured at least 7 cm in length and had at least one major collateral supplying the calf. When IFPB was performed for ischemic lesions, these lesions were usually limited to the digits or small portions of the foot. Forty-seven polytetrafluoroethylene grafts and three autogenous reversed saphenous vein grafts were used.

RESULTS

Ankle brachial pressure index (ABI) increased after bypass grafting by a mean of 0.46. Three-year primary life table patency and limb-salvage rates for primary IFPBs were 73% and 86%, respectively. All eight IFPBs performed after failed tibial bypass grafts remained patent for 2 to 44 months, with patients having viable, healed feet.

CONCLUSION

In the presence of a suitable popliteal artery and limited tissue necrosis, IFPB can have acceptable patency and limb-salvage rates, even when a polytetrafluoroethylene graft is used. Secondary IFPB can be used to achieve limb salvage after failed tibial bypass grafting.

Predictors of long-term patient survival after in situ vein leg bypass

PURPOSE

The objective was to determine the long-term survival rates of patients who undergo distal arterial bypass surgery and to identify the preoperative factors that are predictive of survival.

METHODS

Three hundred fifty-eight consecutive in situ distal leg bypass procedures were performed between July 1986 and December 1995. The relationship between 13 preoperative variables and late survival were determined using both univariate (Kaplan-Meier) and multivariate (Cox regression) statistical techniques.

RESULTS

The cumulative survival rates at 1, 3, 5, and 7 years were 86.6% +/- 2.0%, 63.2% +/- 3.0%, 46.9% +/- 3.4%, and 35.3% +/- 3.8%, respectively. Using Cox regression, four significant variables were found to be associated with lower late survival rates: male gender, diabetes, chronic renal insufficiency (patients with creatinine levels greater than or equal to 1.7 mg/dl or 150 SI units), and a history of cerebrovascular disease (p < 0.001 for model). When none of these four variables were present, the predicted 5-year survival rate was 71%, whereas the survival rate was reduced to 43% to 60% when one was present, 23% to 42% when two were present, 8% to 22% when three were present, and 2% when all four were present.

CONCLUSIONS

This study defines the long-term survival rates in a cohort of patients after undergoing distal bypass surgery and demonstrates that certain preoperative factors are predictive of late survival. Knowledge of these factors may be useful to assist in individual operative decisions between aggressive attempts at distal revascularization versus primary amputation.

Polytetrafluoroethylene bypasses to infrapopliteal arteries without cuffs or patches: a better option than amputation in patients without autologous vein

PURPOSE

This study was undertaken to evaluate our results of polytetrafluoroethylene (PTFE) tibial and peroneal artery bypasses done for limb salvage.

METHODS

Within a group of patients undergoing infrainguinal limb salvage bypasses at our institution between January 1986 and May 1995, 63 patients faced an immediate amputation, had no autologous vein on duplex examination and operative exploration, and had only a tibial or peroneal artery as an outflow vessel for bypass. Most of these patients (82%) had two or more prior ipsilateral infrainguinal bypasses. These 63 patients underwent 66 PTFE bypasses to a tibial or peroneal artery without a distal anastomotic vein cuff or an adjunctive arteriovenous fistula. Our results were then compared with those reported from infrapopliteal (crural) bypasses performed with alternate autologous vein sources or PTFE in conjunction with various recommended adjuncts.

RESULTS

The 3- and 5-year cumulative primary graft patency rates for our PTFE infrapopliteal bypasses were 39%+/-7% and 28%+/-9%, respectively. Secondary graft patency rates were 55%+/-8% and 43%+/-10% at 3 and 5 years, respectively. Limb salvage rates were 71%+/-7% at 3 years and 66%+/-8% at 5 years. Two-year actuarial patient survival rate was only 67%+/-7%.

CONCLUSIONS

These results indicate that a PTFE bypass to an infrapopliteal artery remains a worthwhile option in patients without usable autologous vein. The secondary patency and limb salvage rates were acceptable in this setting and were not significantly different from the best results reported with prosthetic tibial/peroneal bypasses with distal vein cuffs or patches (74% at 1 year; 58% at 3 years), arteriovenous fistulas (71% at 1 year) or composite arm vein grafts (39% and 29% at 3 and 5 years, respectively).

The current status of prosthetic-vein composite grafts for lower extremity revascularization

When infrageniculate lower extremity vascular reconstructions are required in the face of inadequate or insufficient autogenous vein, prosthetic-vein composite grafts remain a viable alternative. Graft patency and limb salvage for composite grafts are intermediate between those of completely autogenous and prosthetic bypasses alone. The sequential technique may offer superior patency in patients with the appropriate anatomy. The addition of adjunctive techniques such as a distal arteriovenous fistula and/or anticoagulation may further improve results. An algorithm illustrating the proper role of composite grafts for distal lower extremity reconstructions is shown in Figure 6. Any significant interval of patency is important in this group of patients in whom limb salvage can often be achieved by healing ischemic lesions and in whom overall life expectancy is limited.

Anastomosis over a stent for heavily calcified arteries

In this report we describe the use of an indwelling stent for end-to-end anastomosis of an arterial prosthesis. Designed as an alternative to conventional suturing in patients with heavily calcified arteries harvested from human cadavers. After the prosthesis is introduced into the artery, an angioplasty balloon catheter is inflated to expand the Palmaz stent and press the prosthesis against the calcified wall of the popliteal artery. From January 1993 to February 1994 we used this technique for end-to-end anastomosis of a polytetrafluoroethylene graft on the popliteal artery in six patients with extensive circumferential calcification of the popliteal artery. In all patients surgery was indicated to avoid amputation and no other method was suitable (no available vein graft, poor runoff). Stent anastomosis was successful in all six patients with no postoperative complications. Intraoperative controls using arteriography and angioscopy and postoperative Doppler ultrasound studies were normal in all patients. During follow-up, graft occlusion occurred in two patients at 10 and 14 months, respectively. Three patients died after control studies at 2, 6, and 8 months had shown the grafts to be patent. No false aneurysms were detected by clinical examination or ultrasound imaging. Although our data do not allow assessment of long-term outcome, this study demonstrates the feasibility of stent anastomosis in patients with extensive, circumferential calcification of the popliteal artery.

Femoropopliteal bypass with either adequate ipsilateral reversed saphenous vein or obligatory polytetrafluoroethylene

The results are presented of a 10-year experience with 312 femoropopliteal bypasses performed in 285 patients using ipsilateral autologous reversed greater saphenous vein when available and adequate and polytetrafluoroethylene (PTFE) when not. The indications for operation were severe claudication in 121 (39%), rest pain in 95 (30%), and minor tissue loss in 96 (31%) limbs. There were 235 (75%) saphenous vein bypasses, of which 157 were above and 78 below the knee, and 77 (25%) PTFE bypasses, 58 above and 19 below the knee. Of these, 232 (79%) saphenous vein and 62 (21%) PTFE bypasses were primary procedures. The 30-day mortality rate was 3% (7/285) and the 30-day amputation rate was 2% (6/312). Overall, 24 (10%) saphenous vein and 30 (39%) PTFE grafts ultimately failed. The cumulative primary patency of all bypasses was 77% +/- 4% (mean +/- 1 SE) (85% to 69%, 95% confidence interval) at 3 years and 75% +/- 4% (86% to 64%) at 5 years. Saphenous vein primary patency was superior to that of PTFE at 3 years, 87% +/- 4% (97% to 77%) vs. 54% +/- 12% (65% to 41%), (p < 0.01), and at 5 years, 81% +/- 6% (96% to 67%) vs. 48% +/- 16% (63% to 33%) (p < 0.01). Above-knee saphenous vein bypass primary patency was slightly better than below-knee patency at 3 years, 89% +/- 4% vs. 84% +/- 6%, and at 5 years, 83% +/- 7% vs. 80% +/- 8%. This was superior to above-knee PTFE patency at 3 years, 54% +/- 14%, and at 5 years, 34% +/- 16% (p < 0.01). The overall PTFE failure rate was three to four times that of the saphenous vein rate. These results strongly support the use of autologous greater saphenous vein for all femoropopliteal bypasses when it is available and of good quality. PTFE grafts are valuable secondary conduits when the vein is not available or is inadequate. This series was not randomized since PTFE was used only in patients with inadequate or unavailable ipsilateral greater saphenous veins. When this protocol was followed, the patency rate for greater saphenous vein was excellent and its use is recommended for femoropopliteal bypass when it is available and of good quality.

PTFE bypass grafting to isolated popliteal segments in critical limb ischaemia

Although the quality of the distal run-off has been considered as an important factor affecting the success of bypass grafting, reasonable results have nevertheless been reported for bypass grafts to a popliteal artery with no direct communication with the tibial or peroneal vessels (isolated popliteal segment, IPS). The use of autogenous vein has produced the best results in this situation with most authors finding polytetrafluoroethylene (PTFE) less satisfactory. Improved results have nevertheless been shown for femoropopliteal and femorotibial PTFE grafts by the incorporation of vein patches into the anastomoses. In this paper, the influence of this technique on the patency of PTFE grafts to IPS is evaluated. Thirty-three PTFE grafts to an IPS and 67 to the below knee (BK) popliteal artery with one or more run-off vessels were studied. All IPS grafts were carried out for limb salvage and in the BK popliteal group, 46 (69%) were for limb salvage and 21 (31%) were for severe claudication. Groups were matched in terms of age, smoking history and prevalence of diabetes mellitus. Cumulative patency rates of 84% at 1 year and 76% at 3 years were achieved in the IPS group compared to 90 and 81% for the BK popliteal group with one or more run-off vessels. Using the Taylor patch technique, comparable 3 year patency rates can be expected for PTFE grafts to IPSs and to BK popliteal arteries with patient tibial or peroneal run-off.